Stimulus recency has a strong effect on both behavior and
neural responses. Its effects on neural responses have been
most closely studied in the visual system in inferotemporal
cortex (IT) in which recency gives rise to suppressed
responses by a phenomenon known as repetition suppression.
This observation has led to many possible explanations of
how repetition suppression arises in the visual system. Here,
we explore three of them: (1) top-down, (2) bottom-up and (3)
independently in each brain region. Each of these accounts
makes different predictions about the pattern of effects at
different stages in visual processing for cases in which the
stimulus either is or is not a match for the location or the
identity of the preceding stimulus. We tested these predictions
by recording from neurons in IT and V2, two separate stages
of processing, while monkeys viewed displays of repeated
and non-repeated image sequences.